nsfw mark api

repos/generation_repo.py

@@ -131,6 +131,16 @@ class GenerationRepo:
             )
             return True
 
+    async def mark_nsfw(self, generation_id: str, is_nsfw: bool) -> bool:
+        if not ObjectId.is_valid(generation_id):
+            return False
+        
+        res = await self.collection.update_one(
+            {"_id": ObjectId(generation_id)},
+            {"$set": {"nsfw": is_nsfw}}
+        )
+        return res.modified_count > 0
+
     async def get_usage_stats(self, created_by: Optional[str] = None, project_id: Optional[str] = None) -> dict:
         """
         Calculates usage statistics (runs, tokens, cost) using MongoDB aggregation.